<template>
    <div class="article-container">
        <!-- 导航栏 -->
        <van-nav-bar class="page-nav-bar" left-arrow title="极客园" @click-left="$router.back()"></van-nav-bar>
        <!-- /导航栏 -->

        <div class="main-wrap">
            <!-- 加载中 -->
            <div class="loading-wrap" v-if="loading">
                <van-loading color="#3296fa" vertical>加载中</van-loading>
            </div>
            <!-- /加载中 -->

            <!-- 加载完成-文章详情 -->
            <div class="article-detail" v-else-if="article.title">
                <!-- 文章标题 -->
                <h1 class="article-title">{{ article.title }}</h1>
                <!-- /文章标题 -->

                <!-- 用户信息 -->
                <van-cell class="user-info" center :border="false">
                    <van-image class="avatar" slot="icon" round fit="cover" :src="article.aut_photo" />
                    <div slot="title" class="user-name">黑马头条号</div>
                    <div slot="label" class="publish-date">{{ article.pubdate | relativeTime }}</div>
                    <!-- <FollowUser :isFollowed="article.is_followed" :userId="article.aut_id" class="follow-btn"
                        @update_isFollowed="article.is_followed = $event">
                    </FollowUser> -->
                    <FollowUser v-model="article.is_followed" :userId="article.aut_id" class="follow-btn">
                    </FollowUser>
                </van-cell>
                <!-- /用户信息 -->

                <!-- 文章内容 -->
                <div class="article-content markdown-body" v-html="article.content" ref="article_content"></div>
                <van-divider>正文结束</van-divider>
                <!-- /文章内容 -->

                <!-- 评论文字 -->
                <van-cell title="评论" />
                <!-- /评论文字 -->

                <!-- 文章评论 -->
                <ArticleComment :source="article.art_id" :list="commentList" @onReplyClick="replyClick">
                </ArticleComment>
                <!-- /文章评论 -->

                <!-- 底部区域 -->
                <div class="article-bottom">
                    <van-button class="comment-btn" type="default" round size="small" @click="isPostShow = true">写评论
                    </van-button>
                    <van-icon name="comment-o" :badge="article.comm_count" color="#777" />
                    <CollectArticle v-model="article.is_collected" :art_id="article.art_id" />
                    <LikeArticle v-model="article.attitude" :art_id="article.art_id"></LikeArticle>
                    <van-icon name="share" color="#777777"></van-icon>
                </div>
                <!-- /底部区域 -->

                <!-- 发布评论弹出层 -->
                <van-popup v-model="isPostShow" position="bottom">
                    <CommentPost :target="article.art_id" @postSuccess="onPostSuccess"></CommentPost>
                </van-popup>
                <!-- /发布评论弹出层 -->
            </div>
            <!-- /加载完成-文章详情 -->

            <!-- 加载失败：404 -->
            <div class="error-wrap" v-else-if="errStatus === 404">
                <van-icon name="failure" />
                <p class="text">该资源不存在或已删除！</p>
            </div>
            <!-- /加载失败：404 -->

            <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
            <div class="error-wrap" v-else>
                <van-icon name="failure" />
                <p class="text">内容加载失败！</p>
                <van-button class="retry-btn" @click="loadArticle">点击重试</van-button>
            </div>
            <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
        </div>

        <!-- 评论回复 -->
        <van-popup v-model="isReplyShow" position="bottom" :style="{ height: '100%' }">
            <CommentReply :comment="currentComment" @close="isReplyShow = false"></CommentReply>
        </van-popup>
        <!-- /评论回复 -->
    </div>
</template>
  
<script>
import { getArticlesById } from '../../api/article'
import { ImagePreview } from 'vant'
import FollowUser from '../../components/follow-user.vue'
import CollectArticle from '../../components/collect-article.vue'
import LikeArticle from '../../components/like-article.vue'
import ArticleComment from './components/article-comment.vue'
import CommentPost from './components/comment-post.vue'
import CommentReply from './components/comment-reply.vue'

export default {
    name: 'ArticleIndex',
    components: {},
    props: {
        articleId: {
            type: [Number, String, Object],
            required: true
        }
    },
    data() {
        return {
            article: {},
            loading: true,
            errStatus: 0,
            isPostShow: false,
            commentList: [],
            isReplyShow: false,
            currentComment: {},
        }
    },
    provide: function () {
        return {
            article_id: this.articleId
        }
    },
    created() {
        this.loadArticle()
    },
    methods: {
        async loadArticle() {
            this.loading = true
            try {
                // if (Math.random() > 0.5) {
                //     JSON.parse('abc')
                // }
                const { data } = await getArticlesById(this.articleId)
                this.article = data.data
                setTimeout(() => {
                    this.previewImage()
                }, 0)
            } catch (err) {
                if (err.response && err.response.status === 404) {
                    this.errStatus = 404
                }
            }
            this.loading = false
        },
        previewImage() {
            const articleContainer = this.$refs.article_content
            const imgs = articleContainer.querySelectorAll('img')
            const images = []
            imgs.forEach((img, index) => {
                images.push(img.src)
                img.addEventListener('click', () => {
                    ImagePreview({
                        images,
                        startPosition: index,
                    })
                })
            })
        },
        onPostSuccess(data) {
            this.isPostShow = false
            this.commentList.unshift(data.new_obj)
        },
        replyClick(comment) {
            this.isReplyShow = true
            this.currentComment = comment
        }
    },
    components: {
        FollowUser,
        CollectArticle,
        LikeArticle,
        ArticleComment,
        CommentPost,
        CommentReply
    }
}
</script>
  
<style scoped lang="less">
@import './github-markdown.css';

.article-container {
    .main-wrap {
        position: fixed;
        left: 0;
        right: 0;
        top: 92px;
        bottom: 88px;
        overflow-y: scroll;
        background-color: #fff;
    }

    .article-detail {
        .article-title {
            font-size: 40px;
            padding: 50px 32px;
            margin: 0;
            color: #3a3a3a;
        }

        .user-info {
            padding: 0 32px;

            .avatar {
                width: 70px;
                height: 70px;
                margin-right: 17px;
            }

            .van-cell__label {
                margin-top: 0;
            }

            .user-name {
                font-size: 24px;
                color: #3a3a3a;
            }

            .publish-date {
                font-size: 23px;
                color: #b7b7b7;
            }

            .follow-btn {
                width: 170px;
                height: 58px;
            }
        }

        .article-content {
            padding: 55px 32px;

            :deep(p) {
                text-align: justify;
            }
        }
    }

    .loading-wrap {
        padding: 200px 32px;
        display: flex;
        align-items: center;
        justify-content: center;
        background-color: #fff;
    }

    .error-wrap {
        padding: 200px 32px;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        background-color: #fff;

        .van-icon {
            font-size: 122px;
            color: #b4b4b4;
        }

        .text {
            font-size: 30px;
            color: #666666;
            margin: 33px 0 46px;
        }

        .retry-btn {
            width: 280px;
            height: 70px;
            line-height: 70px;
            border: 1px solid #c3c3c3;
            font-size: 30px;
            color: #666666;
        }
    }

    .article-bottom {
        position: fixed;
        left: 0;
        right: 0;
        bottom: 0;
        display: flex;
        justify-content: space-around;
        align-items: center;
        box-sizing: border-box;
        height: 88px;
        border-top: 1px solid #d8d8d8;
        background-color: #fff;

        .comment-btn {
            width: 282px;
            height: 46px;
            border: 2px solid #eeeeee;
            font-size: 30px;
            line-height: 46px;
            color: #a7a7a7;
        }

        .van-icon {
            font-size: 40px;

            .van-info {
                font-size: 16px;
                background-color: #e22829;
            }
        }
    }
}
</style>